The operator control of devices appertaining to consumer electronics, such as television sets or video recorders for example, can be simplified for the user by voice control. For instance, it is known to use voice control for changing device settings, executing operator-control functions, such as for example choice of a station, or performing programming operations.
For this purpose, the operator-control commands spoken by the user are initially detected as sound signals, converted into electric signals and digitized. The digitized voice signals are then fed to a speech recognition system. The speech recognition is usually based here on an acoustic model and a speech model. The acoustic model uses a large number of speech patterns, with mathematical algorithms being used to indicate the words which acoustically best match a spoken word. The speech model in turn is based on an analysis in which it is established on the basis of a large number of document samples in which context and how often certain words are normally used.
Current systems provide that the operator-control commands are spoken into the microphone integrated in a remote control unit. Deterioration of the recognition rate caused by disturbing background noises is prevented by the remote control unit being held directly in front of the user's mouth. However, as in the case of conventional remote control units, this requires that the user still has to pick up the remote control unit. Convenience can be enhanced if, for speech input, one or more microphones are provided in the device appertaining to consumer electronics, so that the user can carry out operator control from any desired place in the room without taking along the remote control unit. The required suppression of background disturbances can in this case take place by the use of special microphone arrays and methods such as “statistical beam forming” or “blind source separation”. However, the device being operated is not capable of determining which speech inputs are made by the current user. It is therefore not possible to respond only to these operator-control commands but to ignore utterances by other persons.
A further attempted way of enhancing user convenience is the automatic buffer storage of television programs on hard disks integrated in televisions or settop boxes. After an analysis of the viewing habits, in this case the programs or types of programs which the user has previously chosen regularly are automatically recorded. If the user then switches on his television at any time, he can, with a certain degree of probability, view his favourite programs. However, in the analysis is impaired by the fact that it is not possible to distinguish which user operates the television at which time.